Dear Prof. Rudstam,

I am responding to a posting on "fish-ecology" by Dr. Tyler who mentioned
you have developed a fish hydroacoustic monitoring system.

I am working on the fisheries ecology of the Salton Sea, California's
largest and most endangered lake. It is a hypersaline, hypereutrophic body
of water near the Mexican border dominated by tilapia, an exotic species
from Africa, but has three other marine species (orangemouth corvina, sargo,
gulf croaker). The salinity is 40 ppt and rising endangering all of the
species except the tilapias. In the past few years, catastrophic bird kills
(thousands of grebes and pelicans) have died, blamed on diseased fish.

We are trying to get absolute densities per meter of the inlet rivers and in
the lake. We've proposed to use a Smith-Root electrofisher for high
salinities, but want to also investigate hydroacoustics. We're planning a
large gill net and aquatic biology sampling program to correlate the
length-based and age-based models and environmental parameters.

I can imagine how terribly busy you are, but any assistance at all you can
offer in the technology you and others have developed to assist us would be
most appreciated. We're dealing with an ecosystem that one writer has called
"an environmental time bomb".

Best regards, BCP
_______________________________________________________
Barry Costa-Pierce, Ph.D (Oceanography, University of Hawaii 1984)
Fellow, Elected 1996, American Institute of Fishery Research Biologists
SRFP Lecturer in Global Sustainability
Department of Environmental Analysis and Design
School of Social Ecology
University of California, Irvine

222 South Helix Avenue,   Suite  # 1
Solana Beach, California 92075  USA
Phone: 619-259-9029
Fax:     619-259-3237
e-mail:  [log in to unmask]
____________________________________________________